Two leading Senate Democrats introduced a bill Thursday that would strictly limit the use of arbitration, a process used to resolve legal disputes that is often stacked against consumers.

The bill, introduced by Senator Patrick J. Leahy, Democrat of Vermont, and co-sponsored by Senator Al Franken, Democrat of Minnesota, would prevent civil rights cases, employment disputes and other crucial lawsuits from being forced into arbitration, where judges and juries have been replaced by arbitrators who commonly consider the companies their clients.

“Legal fine print tips the scales against us,” Mr. Leahy said. “It is forcing consumers into private arbitration, denying us of our constitutional right to protect ourselves in court.” Regulators and lawmakers have been pushing to prevent companies, large and small, from inserting arbitration clauses in contracts. It is virtually impossible to rent a car, open a bank account, get a job or enroll an elderly parent in a nursing home without signing away the right to take a case to court.

Embedded in tens of millions of contracts, the clauses prevent Americans from joining in class-action lawsuits, the only realistic way that an individual can do battle with a wealthy corporation.

The prevalence of arbitration clauses was the subject of a series of articles in The New York Times last year. Since then, efforts to rein in the practice have gained momentum, giving rise to several legislative proposals and calls on the Obama administration to use executive authority to bar federal contractors from using arbitration.

In its investigation, based on thousands of court records and interviews with hundreds of lawyers, judges and arbitrators in 35 states, The Times found that by using arbitration clauses corporations can circumvent the courts and quash challenges to discrimination, predatory lending and even wrongful death.

Once their class action is derailed, few people, The Times found, go to arbitration at all. Those who do confront a system that gives companies so much latitude that in some cases they can require customers to go to Christian arbitration, which is bound by the Bible rather than state or federal law.

The bill introduced Thursday is likely to face intense opposition, in Congress and from the business lobby. Other bills, including one that aimed to protect exempt service members from arbitration, have met fierce resistance from banks and the U.S. Chamber of Commerce.

Behind the latest bill is an acknowledgment that critical laws resulting from the civil rights and disability rights movements are fatally undermined by arbitration.

If enacted, the bill would make claims brought under laws like the Family Medical Leave Act and the Fair Labor Standards Act exempt from arbitration.

In a statement Thursday, Mr. Leahy highlighted the example of a woman who lost her job after a miscarriage prevented her from going to work, a potential violation of the Family and Medical Leave Act. Her case was pushed out of court and into arbitration.

“Our legislation is common-sense reform that will help to restore Americans’ right to challenge unfair practices by corporations, and it needs to be passed into law,” Mr. Franken said.

A version of this article appears in print on , on Page B4 of the New York edition with the headline: Arbitration Is Target of New Bill in Senate. Order Reprints | Today’s Paper | Subscribe